<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>案例一</title>
    <style>
        table,tr,td{
            border: 1px red solid;
        }
        td{
            text-align: center;
        }
    </style>
</head>
<body>
<form action="#" method="get">
    <table>
        <tr>
            <td>用户:</td>
            <td><input type="text" name="username"></td>
        </tr>
        <tr>
            <td>密码:</td>
            <td><input type="password" name="password"></td>
        </tr>
        <tr>
            <td colspan="2"><button type="submit">注册</button></td>
        </tr>
    </table>
</form>
</body>
</html>